METHOD AND APPARATUS FOR CLEANING REFUSE BINS

Abstract: The invention relates to a method in waste collection effected by means of a waste container truck. A waste container truck is used for dumping dumpsters (1) into the waste container of a waste container truck by mounting at least one dumpster at a time in engagement with a waste container truck from the locations thereof. The contents of a waste container (7) are carried by a waste container truck to a next operation in waste treatment. At least the interior of the dumpster (1) is cleaned while in engagement with a waste container truck immediately after dumping the dumpster (1) prior to replacing it in its location. The invention relates also to an apparatus for carrying out the method.

Description: METHOD AND APPARATUS FOR CLEANING REFUSE BINS, The present invention relates to a method in waste collection effected by means of a waste container truck, wherein a waste container truck is used for dumping dump- sters into the waste container of a waste container truck by mounting at least one dumpster at a time in engagement with a waste container truck from the locations thereof, whereby the contents of the waste container are advanced to a next operation in waste treatment, whereby at least the interior of the dumpster is cleaned while in engagement with the waste container truck immediately after dumping the dumpster which is still essentially in a dumping position prior to replacing it in its location, and whereby the cleaning agent used in cleaning is essentially returned into a cleaning agent circulation system included in the waste container truck separately from the waste held in the waste container. In a prior art waste collection method as described above, the cleaning of dumpsters is effected in such a manner that the waste container truck is followed by a separate washing vehicle, which picks up the dumpsters dumped by the waste container truck for a washing treatment immediately after dumping the dumpster into the waste container truck. As for the prior art, reference is made to publications DE-3207508 and DE-2590241. The above-described prior known process involves several drawbacks. First of all, the collec¬ tion and washing operations always require two separate vehicles with individual drivers and, naturally, this requires major investments in vehicles themselves and mechanisms used therein. On the other hand, the operation is expensive as the process requires a fairly large personnel. Regarding the functionality, the described process is relatively slow as the waste container truck must always wait for the conclusion of a washing operation since, naturally, the process can only be applied by making sure that the dumpster is empty when the washing is performed. Thus, the waste container truck is not able to exploit its full capacity. The above procedural drawbacks have further led to the problematic situation that dumpsters will be washed quite infrequently even if there is an apparent need for washing. Recently, the need for washing dumpsters has * increased especially for the reason that the assortment of e.g. biowaste has been undertaken more extensively into separate dumpsters whereby, for hygienic and especially for deodorization reasons, the need for washing has considerably in¬ creased particularly during warm seasons. An object of this invention is to introduce a method which is capable of most effectively eliminating the above-described drawbacks and, thus, of improving the current state of the art. The method is principally characterized in that the method is applied in a waste container truck which is provided with a per se known waste bin or a like for receiving the waste coming from a dumpster prior to delivering such waste from the waste bin into a waste container, whereby the waste bin or a like is set in flow communication with a cleaning agent circulation system. Thus, the method is based on the feature that a waste container truck is provided with a cleaning agent for cleaning at least the interior of a dumpster immediate¬ ly after dumping it and not until after this cleaning operation is the dumpsater replaced in its location. Hence, both the operation for dumping a dumpster and at least the internal cleaning of a dumpster are performed immediately one after the other and not until after this is the dumpster replaced in its location. It is obvious that the above comprehensive method is first of all capable of achieving substantial savings in investments as well as in personnel expen¬ ses. It should also be noted that the level of hygiene rises and the odour problems are reduced substantially as the dumpster can be washed at least over its interior part at a sufficient frequency, if necessary, even after each dumping operation in a speedy and reliable fashion. The appended dependent claims directed to a method set forth a few preferred embodiments for a method of the invention. The invention relates also to an apparatus set forth in the preamble of the independent claim directed to an apparatus in waste collection carried out by means of a waste container truck. A waste container truck, which is fitted with an apparatus of the invention, includes a waste container for the collection of waste by dumping dumpsters sequentially into the waste container adapted to be performed from the locations of dumpsters by using elements included in the waste container truck for taking hold of a dump¬ ster, for placing it in a dumping position for deliver- ing the waste into the waste container and for removing the dumpster from its engagement with the container truck. An apparatus of the invention is principally characterized in that said apparatus is included in a waste container truck, which is provided with a per se known waste bin or a like for receiving the waste coming from a dumpster prior to advancing it from the waste bin into a waste container and that the waste bin is connected to a cleaning agent circulation system by means of a port system included in the waste bin. The above-described apparatus is capable of offering the previously explained procedural benefits. The appended dependent claims directed to an apparatus set forth a few preferred embodiments for an apparatus of the invention. The invention will be described in more detail in the following specification with reference made to the accompanying drawings, which illustrate one comprehen¬ sive procedural and mechanical solution. In the drawings, Figs. 1-4 depict schematically and sequentially the application of a method of the invention in a side view, Fig. 5 shows a perspective view of a first embodiment for a washing agent supply unit, Fig. 6 shows a second embodiment for a washing agent supply unit in a plan view, and Fig. 7 is a vertical section showing a communica¬ tion between a waste bin and a water receiver. Referring especially to Figs. 1-4, a dumpster 1 to be dumped is lifted in Fig. 1 to a dumping position by means of actuators 2 serving as elements for grabbing a dumpster and for setting the same in a dumping position and the dumpster is dumped into a waste container 7 included in a garbage truck. This sequence is not described in more detail in connection with this application as it involves technology prior known to a person skilled in the art. The dumping is followed by turning nozzle assemblies 4, 8a and 8b, which are mounted in connection with a dumpster supporting bracket 3 included in the vehicle and which, together with body assemblies essentially associated therewith, provide a washing agent supply unit 23 (Fig. 5) , to a washing position in such a manner that washing operations of the dumpster 1 can be performed through the nozzle assemblies 4, 8a, 8b. The dumpster 1 is in the same position as it was during the dumping of waste, in other words carried by the actuators 2 and supporting bracket 3 in such a manner that the mouth opening of said dumpster 1 is directed obliquely down towards a waste bin included in the waste container truck. In the first sequence of a cleaning operation, a solvent unit 5, fitted in connection with a waste container truck and containing a solvent pumping unit, is operated for delivering the solvent used for preliminary washing by way of tubes and hoses 6 in¬ cluded in a pipe system to a first nozzle assembly 8a. In the nozzle assembly 8a, the solvent atomizes and sprays as a mist onto the interior walls of a dump¬ ster 1. Fig. 2 depicts the actual washing operation constitut- ing a second sequence in practicing the method. At this point, the access of a solvent to the first nozzle assembly 8a is denied. The waste container truck is provided with a power unit 9, including a smallish water tank 9a and a high-pressure water pump 9b. Water is delivered from the water tank 9a included in the power unit 9 by way of tubes and hoses 13 included in a pipe system to a second nozzle assembly 4. The water is sprayed at a high pressure through the nozzle assembly 4 into the interior of a dumpster to be washed. The spent washing water flows from the dumpster 1 into a waste bin 14 included in the waste container truck, i.e. into a pocket that receives the waste coming from the dumpster 1 for advancing it into the waste container 7. From the waste bin 14 the washing water continues to flow into a water receiver 15 located below the waste bin. Between the waste bin 14 and the water receiver 15 is established a washing agent flow communication (Fig. 7) , e.g. by means of a closeable and openable port system or a like, included in the waste bin and set in communication with the water receiver 15. This construction can be obtained in several different ways, one preferred approach being depicted in Fig. 7. A port system 28 is included in each flank of the waste bin 14 at the vertically lowest points in vertical side surfaces 32 of said waste bin 14. Ports 28a included in the port system 28 (Fig. 7 depicts the construction at one of the flanks) are both provided with a flap 29, serving as a closure means and connected to the rod of a piston 31 included in a pressurized-medium operated cylinder-piston assembly 10. The port system 28 is opened by shifting said piston 31 to the left in Fig. 7, which depicts the port system 28 in a closed position. The water receiver 15 is likewise arranged to include two sections, said sections being connected to hoses or tubes 16a which are connected to a filter pump 18. The most important feature in the construction is that the waste bin can operate normally as a waste collec¬ tion floor as well as in the passage of waste into the waste container. From the water receiver 15 the washing agent is vacuumed by means of the filter pump 18 by way of hoses and tubes 16a, 16b included in the pipe system as well as through filters 17 and 19 back into the water tank 9a for reuse. Thus, the water soiled in the actual washing operation is filtered for reuse, the apparatus for applying the method comprising an internal recycling system as well as a filter assembly for the washing agent purification constituted by the filters 17 and 19. On the other hand, Fig. 3 depicts the final or a third sequence included in the washing operation. After the action described in Fig. 2 and in the respective part of the text has progressed to the point that a desired washing result has been achieved, the entry of water into the dumpster 1 is prevented. The waste container truck is fitted with a disinfectant tank 21, which includes a disinfectant pumping unit and which is used for carrying the disinfectant to a third nozzle assembly 8b by way of tubes and hoses 22 included in the pipe system. In the nozzle assembly 8b, the disinfectant atomizes and sprays in the form of a mist onto the internal walls of the dumpster 1. After the spraying of disinfectant the washing of a dumpster is finished and the actuators 2 can be operated for lowering the dumpster down on the ground at least in the proximity of its location, to which it can be maneuvered manually. Fig. 4 depicts yet a situation, wherein just the filter pump 18 is in operation for vacuuming the spent washing water and/or excessive disinfectant possibly retained in the waste bin 14 back into the tank 9a. Referring especially to Figs. 1-4, the solid line indicates the part of a pipe system or a like in active operation in this particular sequence, while the other sections of a pipe system are indicated by dashed lines. Thus, in reference to what is described above, a method of the invention is characterized in that the cleaning is performed with a cleaning agent which is placed in connection with a waste container truck apart from the waste held in the waste container 7. Further according to the method, a cleaning agent used in cleaning is essentially replaced in connection with a waste container truck apart from the waste held in the waste container 7. Also the fact that the cleaning agent to be returned in connection with a waste container truck is cleaned for reuse is an essential feature in the invention. Figs. 1-4 explicitly depict the cleaning as a three- sequence process. It is obvious that the invention can also be applied in a single sequence simply by performing the internal washing of a dumpster with a washing water admixed with a disinfecting washing agent, i.e. without separate preliminary washing and a disinfecting sequence. Thus, an apparatus of the invention comprises a container assembly, including a solvent unit 5, a water tank 9a, and a disinfectant unit 21. The apparatus comprises also a washing agent supply unit 23, including nozzle assemblies 4, 8a and 8b. Furthermore, the apparatus includes a water receiver 15 serving as a washing agent receptacle and a filtering assembly 17, 18, 19. Naturally, the apparatus comprises a pipe system or a like for carrying the components of a washing agent from the container assembly 5, 9a, 21 to the washing agent supply unit to be sprayed into the dumpster 1 through the nozzle assembly intended for that particular component. Respectively, the pipe system also includes a section of said pipe system for carrying the spent washing agent through the filtering assembly from the washing agent receptacle 15 into the container assem¬ bly, especially into the water tank 9a, for reuse. As depicted especially in the embodiments shown in Figs. 5 and 6, the washing agent supply unit 23 is mounted on a supporting bracket 3 having the configura¬ tion of a U-shaped girder whose upper edge is fitted with a gear assembly 20, 26 (Figs. 1 and 6) abutting against the upper edge of a dumpster in the operating position of said supporting bracket 3. Thus, the washing agent supply unit 23 is adapted to be rotatable by means of rotating elements (not shown) between the legs of the downwardly opening U-shape of said support¬ ing bracket 3 and can be rotated relative to the supporting bracket 3 to an active position shown in Figs. 5 and 6, whereby all three nozzle assemblies 4, 8a, 8b included in the washing agent supply unit are able to perform the actions included in a required washing cycle. The first and second 8a, 8b are mounted on the mid-section of a supporting arm 27 fitted between the legs of the U-shaped supporting bracket 13 to be rotatable around its longitudinal axis. In a non-operative position, said washing agent supply unit 23 finds such a location relative to the mouth opening of a dumpster so as not to prevent the dumping operation of the contents of a dumpster into the waste bin 14. Referring particularly to the second washing liquid nozzle assembly 4, it can be said to comprise an arched tubular profile, mounted in connec¬ tion with the supporting arm 27 and having its wall provided with a perforation 25 or individual nozzles for producing liquid jets, especially water jets (VS Fig. 6) over a wide periphery along the length of the entire tubular profile. Fig. 6, in particular, depicts an embodiment for the washing agent supply unit 23 comprising two parallel nozzle assembly units 4, 8a, 8b. This type of assembly can be used in garbage truck constructions that are capable of dumping simultaneously two dumpsters side by side. It is obvious that a method and an apparatus of the invention can be applied in a plurality of ways in relation to all available garbage truck constructions. For example, it is possible to include the drying of a dumpster prior to the disinfecting operation. It should be noted that the terms "cleaning" and "cleaning agent" in this context refer definitely to all those component agents that are used in the overall cleaning process, e.g. just drying air. The location refers to a place where a dumpster is normally positioned for receiving waste, e.g. within the yard area or by the roadside. The washing agent supply unit 23 can also be constructed fixedly relative to the supporting bracket 3 in such a way, however, that the supply unit does not prevent the unloading of waste from a dumpster but allows an unimpeded cleaning operation. It is also possible to employ the above-described invention as a part of such a combination which includes not only a supply unit but also separate elements for distributing a cleaning agent over the other surfaces of a waste container truck, e.g. for cleaning the interior of a waste container in addition to that of a dumpster. In this respect, reference is made to the Applicant's co-pending patent application "Method and apparatus in a waste container truck".

Claims: Claims 1. A method in waste collection effected by means of a waste container truck, wherein a waste container truck is used for dumping dump¬ sters (1) into the waste container of a waste container truck by mounting at least one dumpster at a time in engagement with a waste container truck from the locations thereof, whereby - the contents of a waste container (7) are advanced to a next operation in waste treatment, whereby - at least the interior of the dumpster (1) is cleaned while in engagement with the waste container truck immediately after dumping the dumpster (1) which is still essentially in a dumping position prior to replacing it in its location, and whereby the cleaning agent used in cleaning is essentially returned into a cleaning agent circulation system included in the waste container truck separately from the waste held in the waste container (7) , characterized in that the method is applied in a waste container truck which is provided with a per se known waste bin (14) or a like for receiving the waste coming from the dumpster (1) prior to delivering such waste from the waste bin (14) into the waste container (7) , whereby - the waste bin (14) or a like is set in flow com¬ munication with a cleaning agent circulation system. 2. A method as set forth in claim 1, characterized in that a cleaning agent receiver (15) or a like is positioned preferably below the waste bin (14) in flow communication with the waste bin (14) or a like of a waste container truck by way of a port system (28) included in the waste bin (14) or a like. 3. A method as set forth in claim 1, characterized in that a cleaning agent coming from the waste bin (14) or a like into a circulation system and to be returned in connection with a waste container truck is puri ied for reuse. 4. A method as set forth in any of claims 1-3, characterized in that the cleaning is carried out essentially in three sequences, whereby - the first sequence involves a preliminary washing, preferably with a solvent, - the second sequence involves an actual washing, especially a high-pressure washing, preferably with water and - the third sequence involves a disinfecting with a disinfectant, and whereby the cleaning agents spent particularly in the first and second sequences and returned into the circulation system from the waste bin (14) are returned in connection with a waste container truck especially for purifying the same for reuse. 5. An apparatus in waste collection effected by means of a waste container truck, whereby - the waste container truck is fitted with a waste container (7) for the collection of waste by dumping dumpsters (1) sequentially into the waste container (7) adapted to be performed from the location of the dumpsters (1) by using elements (2) included in the waste container truck for taking hold of the dumpster, for placing it in a dumping position in engagement with the waste container truck, for delivering the waste into the waste container and for removing the dumpster from its engagement with the container truck, - the waste container truck is provided with elements (5, 9a, 21; 6, 13, 22; 23; 28; 15; 16a, 16b, 17, 18, 19) for cleaning at least the interior of the dumpster (1) essentially in a dumping position with a cleaning agent while the dumpster is in engagement with the -waste container truck, said elements (5, 9a, 21; 6, 13, 22; 23; 28; 15; 16a, 16b; 17, 18, 19) being essentially adapted to form a closed circulation system for the cleaning agent, characterized in that the apparatus is included in a waste container truck, which is provided with a per se known waste bin (14) or a like for receiving the waste coming from the dumpster (1) prior to advancing it from the waste bin (14) into a waste container (7) and that the waste bin (14) is connected to a cleaning agent circulation system by means of a port system (28) included in the waste bin (14) . 6. An apparatus as set forth in claim 5, wherein the elements for cleaning at least the interior of a dumpster comprise in connection with a waste container truck: a container assembly (5, 9a, 21) for a washing agent, a cleaning agent supply unit (23) , a filtering assembly (17, 18, 19), and a pipe system (6, 13, 22, 16a, 16b) or a like for carrying the cleaning agent from the container assembly to the cleaning agent supply unit (23) and into the container assembly for reuse, characterized in that the waste bin is in communication with a receiver (15) or a like, which is connected by way of a section (16a) of the pipe system to the filtering assembly (17, 18, 19) for purifying the cleaning agent prior to its delivery into the container assembly for reuse. 7. An apparatus as set forth in claim 5 or 6, charac¬ terized in that the cleaning agent supply unit (23) includes a first nozzle assembly (8a) for delivering a preliminary washing agent, preferably a solvent, a second washing liquid nozzle assembly (4) or a like for delivering water, and preferably also a third nozzle assembly (8b) for delivering a disinfectant at least to the internal surfaces of the dumpster (1) , the cleaning being preferably adapted to proceed in three sequences in such a manner that the first sequence involves operation of the first nozzle assembly (8a) for effecting the preliminary washing, then essentially the washing nozzle assembly (4) , and the third sequence preferably involves use of the second nozzle assembly (8b) , and that the pipe system (6, 13, 22, 16a, 16b) or a like includes tube elements for carrying out the above sequences. 8. An apparatus as set forth in any of claims 5-7, characterized in that the cleaning agent supply unit (23) is mounted in engagement with elements (2, 3) included in a waste container truck for grabbing a dumpster and is preferably provided with means for switching the cleaning agent supply unit (23) to an operative position from a non-operative position following the dumping of said dumpster (1) . 9. An apparatus as set forth in claim 5, charac¬ terized in that the port system (28) is adapted to be openable and closeable. 10. An apparatus as set forth in claim 5-8, charac- terized in that the container assembly (5, 9a, 21) comprises three sections, including separate containers for a preliminary washing agent, washing agent and disinfectant. 11. An assembly as set forth in claim 6 or 7, charac¬ terized in that the cleaning agent supply unit (23) includes two or more aggregates of nozzle assemblies (4, 8a, 8b) for carrying out the simultaneous cleaning of two or more dumpsters (1) . 12. An apparatus as set forth in claim 7 or 8, characterized in that the second washing nozzle assembly (4) comprises an arched tubular profile, including a perforation (25) or a like for producing liquid jets, and that the first and third nozzle assemblies (8a, 8b) are included in a supporting arm (27) mounted in connection with the elements (2, 3) for grabbing a dumpster.

Inventors: LEHTIMAEKI PEKKA, LEHTIMAEKI, PEKKA
Applicants: HYDEX OY, LEHTIMAEKI PEKKA, LEHTIMAEKI, PEKKA
Application year: 1994
Main classification: B65F7
IPC codes: B08B9, B65F7